Defective-needle alarm for knitting-machines.



R. W. SCOTT. DEFECTIVE NEEDLE ALARM FOR KNITTING MACHINES. APPLICATION FILED IUNE2I. I9I6'.

IIIIIIIMWIIII Patented June 18, 1918.

* D STATES PATENT OFFICE.

ROBERT W. SCOTT, OF BOSTON, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO SCOTT 8a WILLIAMS, INCORPORATED, A CORPORATION OF MASSACHUSETTS.

DEFECTIVE-NEEDLE ALARM FOR KNITTING-MACHINES.

Specification of Letters Patent. Patented June 18, 1918,

Application filed June 21, 1916. Serial No. 104,910.

To all whom it may concern:

Be it known that I, ROBERT W. SCOTT, a citizen of the United States, residing in Boston, Massachusetta have invented certain Improvements in Defective-Needle Alarms for Knitting-Machines, of which the following is a specification.

The object of my invention is to provide a knitting machine with alarm or stopping mechanism operative on the breakin of a needle butt or like accident which wi 1 prevent the needle from being properlymoved by the needle actuating cams, or otherwise interfere with the orderly operation of the machine.

In the accompanying drawing-- Figure 1 is a top view of suflicient of a knitting machine to illustrate alarm mechanism in accordance with my invention with which said machine is provided;

Fig. 2 is a side elevation of part of the same;

Fig. 3 is a diagrammatic representation of the needles of the machine at the draft point showing the relation thereto of the member which operates the alarm, and

Fig.4 is a top view of the parts shown in In Fig. l ofthe drawing, 1 represents the head of a circular knitting machine, 2 a needle cylinder rotatably mounted therein, and 3 a post at one side of the head upon which post is mounted an ordinary gong 4. Pivotally mounted at 5 upon the head 1 of the machine is a lever 6 having three arms 6*, 6? and 6, the arm 6 being preferably resilient and having thereon a hammer 7 for striking the gong 4.

The lever 6 is acted upon by a spring 8 which tends to move said lever to such position that the end of the arm 6 overlaps the circular plane in which the needles are disposed in the cylinder 2, as shown in Fig. 1, such overlapping end of the arm 6 being located at the point where down draft is imparted to the needles, as shown in Fig. 3, this position of the free end of the arm 6 being determined by contact of a lug 6 on the arm 6 of the lever 6 with one or other of a series of thread guide operating bars m with which, the machine is provided.

When the needles are operating normally they will have no effect upon the overla ping end of the arm 6 of the lever and t e latter will occupy the posltion shown by full lines in Fig. 1, the hammer 7 being then free from contact with the gong 4.

If, however, a needle butt is broken or a needle sufi'ers any other accident which will prevent it from being drawn down to the proper point by the needle actuating cams, such projecting needle (shown at 10 in Fig. 3) W111 strike the overlapping end of the arm 6 and thrust the same outwardly, the movement being continued by momentum until the finger reaches the position shown by dotted lines in Fig. 1, so as to cause the hammer 7 to contact with the gong 4 and sound an alarm, such alarm being repeated on each rotation of the cylinder as long as the defective condition exists.

The operations described take place while the machine is knitting round-and-round, but if to-and-fro-knitting is also to be performed the arm 6 must be withdrawn from the position shown by full lines to that shown by dotted lines in Fig. 1, because, during such to-and-fro knitting, a number of needles normally occupy an elevated position and would therefore strike the projecting end of the arm 6 on each reciprocation. For this reason some means should be employed for withdrawing the finger during reciproeating knitting and restoring it to normal positlon again during round-and-round knitting.

Many devices may be employed for this purpose but in the present instance I have shown the arm 6 of the lever 6 as provided with a projecting end 6 for contact with the beveled upper end 6 of a bar 460 such as employed in the machine shown in my Letters Patent No. 1,152,850, dated September 7th, 1915, for controlling the devices for closing the gap in the latch ring with which such machine is provided, rising and falling movements being imparted to this bar at the proper times by the'cam mechanism shown in said patent.

During round-andaroundknitting the bar 460 occupies the lowered position shown in Fig. 2, but durin to-and-fro knitting said bar occupies an e evated position, the beveled upper end of the bar at such time pushing outwardly upon the end 6 of the arm 6 of the lever 6 and thereby withdrawing the free end of its arm 6" out of the path of the needles.

While I have, in practice, found the simple gong and hammer to provide an effective alarm device, my invention .is not linr' i itled ftherto", asflanielectriclor tame autohence in some of my claims I have used the term emergency dev1ceto'apply to either matic alarm set in operationbymovement o h amfitf m thepe t on v byv fulllinesto that "shown y dotted [lines in' -bits, 'and, after being held there y until a number of succeeding courseshave been knitted, are-transferred to corresponding needlesgfso'as to "form "an inturned welt on the web. In such' mach'ine, any accident which causes a transfer bit to retain its bight of' yarn instead of properly delivering 'itto the needlewhich should receive it,

wvill cause said retained bight to strike and operate the arm 6 in the same manner as does a projecting needle in the machine shownin the drawing.

The arm 6 may also be caused to operate a stop'motion device instead of an alarm,

of such adaptations.

It will befevident-that by locating the hammer and hammer armon the opposite side of the gong'from that shown, in the drawing, the striking of the gong by the hammer-can be effected by the recoil of the i spring 8 instead of; by the push upon the arm nae at can patent may he matinee tor b of the lever 6, and in some cases this disposition of the hammer and hammer arm in respect to the gong may be preferred.

. 1 I claim:

l. The combination of the needles of a knitting machine adapted for both round- 1 Eand-round and to-and-fro knitting, with an ,emergeney device and a lever having one arm which overlaps the normal path of the needles during round-and-round' knitting, and another arm for operating said emergency device, and means forwithdrawing-said lever arm from such overlapping positionduring to-and-fro knitting.

2. The combination of'the needles of a intense knitting machine with an emergency device and a lever having one arm" which overlaps the normal path of the needles, and another arm for operating sa d emergency device,

an intermittently movingelement of the machine, and means whereby said element is, caused to act upon an arm of said lever to withdraw the overlapping portion of the same away from' the path of the needles at intervals.

3. The combination of the needles of a. knitting machine with an emergency device and a lever having one arm which overlaps the normal path of the needles, and another arm for operating said emergency device, yielding means for maintaining said lever arm'in such overlapping relation, a machine element which, by contact with an arm of said lever, serves to limitthe movement of the same in one direction, and a movable element of the machine which acts upon said arm at intervals to move it in the opposite direction and away from the needle path.

4. The combination of the needles of a knitting machine with an emergenc device and a lever having one arm which overlaps the normal path of the needles, and another arm for operating said emergency device, and an operative element of the machine movable to different positions in respect to an arm of said lever, said operative element having a beveled face for acting upon said arm to remove the overlapping arm away from the normal needle path.

5. The combination of the needles of a knitting machine with an emergency device having an actuating member consisting of a pivoted lever having two arms, one of which overlaps the normal path of the needles, resilient means acting on said lever to maintain said arm in such overlapping relation, a machine element acting on the other arm of said lever to limitthe extent of the movement due to such resilient means,

and a movable member of the machine also actingupon said second arm of the lever to withdraw the other arm of the same from the path of the needles at intervals.

In testimony whereof, I have signed my name to this specification.

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